# General Exam-Missed Questions-1

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1. G1A02 On which of the following bands is phone operation prohibited?
A. 160 meters
B. 30 meters
C. 17 meters
D. 12 meters
(B)
2. G1A03 On which of the following bands is image transmission prohibited?
A. 160 meters
B. 30 meters
C. 20 meters
D. 12 meters
• (B)
• The 30 meter band is restricted to CW, RTTY and data transmissions only. Image transmission is also prohibited on the 60 meter band. [97.305]
3. G1A04 Which of the following amateur bands is restricted to communication on only specific channels, rather than frequency ranges?
A. 11 meters
B. 12 meters
C. 30 meters
D. 60 meters
• (D)
• In the US, Amateur Radio is a secondary service to government stations on 60 meters. By limiting amateur operation to specific channels, it is easier for hams to tell when government stations are present and to avoid interfering with them. [97.303(s)]
4. G1A05 Which of the following frequencies is in the General Class portion of the 40 meter band?
A. 7.250 MHz
B. 7.500 MHz
C. 40.200 MHz
D. 40.500 MHz
• (A)
• General Class licensees have access to the following portions of the 40 meter band (f = 300 / 40 = 7.5 MHz): 7.025 - 7.125 MHz on CW/RTTY/data and from 7.175 - 7.300 MHz on CW/Phone/Image. [97.301(d)]
5. G1A06 Which of the following frequencies is in the 12 meter band?
A. 3.940 MHz
B. 12.940 MHz
C. 17.940 MHz
D. 24.940 MHz
• (D)
• Use the formula f = 300 / 12 = 25 MHz to get the approximate frequency range of the 12 meter band. [97.301(d)]
6. G1A07 Which of the following frequencies is within the General Class portion of the 75 meter phone band?
A. 1875 kHz
B. 3750 kHz
C. 3900 kHz
D. 4005 kHz
• (C)
• Although the 75 and 80 meter bands are part of a single amateur band, the difference in wavelength is enough for amateurs to make a distinction between 75 meters at the higher frequencies and 80 meters at the lower frequencies. General Class licensees have access to the following portions of the 75 meter band (f = 300 / 75 = 4.0 MHz): 3.800 - 4.000 MHz on CW/Phone/Image. [97.301(d)]
7. G1A08 Which of the following frequencies is within the General Class portion of the 20 meter phone band?
A. 14005 kHz
B. 14105 kHz
C. 14305 kHz
D. 14405 kHz
• (C)
• General Class licensees have access to the following portions of the 20 meter band (f = 300 / 20 = 15 MHz): 14.025 - 14.150 MHz on CW/Phone/image and from 14.225 - 14.350 MHz on CW/Phone/Image. [97.301(d)]
8. G1A09 Which of the following frequencies is within the General Class portion of the 80 meter band?
A. 1855 kHz
B. 2560 kHz
C. 3560 kHz
D. 3650 kHz
• (C)
• General Class licensees have access to the following portions of the 80 meter band (f = 300 / 80 = 3.75 MHz): 3.525 - 3.600 MHz on CW/RTTY/Data. [97.301(d)]
9. G1A10 Which of the following frequencies is within the General Class portion of the 15 meter band?
A. 14250 kHz
B. 18155 kHz
C. 21300 kHz
D. 24900 kHz
• (C)
• General Class licensees have access to the following portions of the 15 meter band (f = 300 / 15 = 20 MHz): 21.025 - 21.200 MHz on CW/RTTY/data and from 21.275 - 21.450 MHz on CW/Phone/Image. [97.301(d)]
10. G1B08 When choosing a transmitting frequency, what should you do to comply with good amateur practice?
A. Review FCC Part 97 Rules regarding permitted frequencies and emissions?
B. Follow generally accepted band plans agreed to by the Amateur Radio community.
C. Before transmitting, listen to avoid interfering with ongoing communication
D. All of these choices are correct
• (D)
• Choosing a frequency is straightforward: Be sure the frequency is authorized to General class licensees, follow the band plan under normal circumstances, and listen to the frequency to avoid interfering with ongoing communications.
11. G1C01 What is the maximum transmitting power an amateur station may use on 10.140 MHz?
]A. 200 watts PEP output
B. 1000 watts PEP output
C. 1500 watts PEP output
D. 2000 watts PEP output
(A)The general rule is that maximum power is limited to 1500 watts PEP output, although there are exceptions where less power is allowed. One such exception is the 30 meter band, 10.100 - 10.150 MHz, where the maximum power for US hams is 200 watts. (These frequencies are just above the short-wave time broadcasts of WWV and WWVH at 10.0 MHz.) [97.313(c)(1)]
12. G2A04 Which mode is most commonly used for voice communications on the 17 and 12 meter bands?
A. Upper sideband
B. Lower sideband
C. Vestigial sideband
D. Double sideband
• (A)
• Amateurs normally use the upper sideband for 17 and 12 meter phone operation. Whether the upper or lower sideband is used is strictly a matter of convention, and not of regulation, except on 60 meters where USB is required. The convention to use the lower sideband on the bands below 9 MHz and the upper sideband on the higher-frequency bands developed from the design requirements of early SSB transmitters. Although modern amateur SSB equipment is more flexible, the convention persists. If everyone else on a particular band is using a certain sideband, you will need to use the same one in order to be able to communicate.
13. G2E08 What segment of the 80 meter band is most commonly used for data transmissions?
A. 3570 – 3600 kHz
B. 3500 – 3525 kHz
C. 3700 – 3750 kHz
D. 3775 – 3825 kHz
• (A)
• The FCC’s rules specify where RTTY and data transmissions allowed, but the band plans tell you where such signals are usually found. Table G2E04 gives the band plan calls for RTTY operation as from 3570 to 3600 kHz on 80 meters.
14. G3A01 What is the sunspot number?
A. A measure of solar activity based on counting sunspots and sunspot groups
B. A 3 digit identifier which is used to track individual sunspots
C. A measure of the radio flux from the Sun measured at 10.7 cm
D. A measure of the sunspot count based on radio flux measurements
• (A)
• A number of observatories around the world measure solar activity. A weighted average of this data is used to determine the International Sunspot Number (ISN) for each day. These daily sunspot counts are used to produce monthly and yearly average values. The average values are used to see trends and patterns in the measurements.
15. G3A14 How are radio communications usually affected by the charged particles that reach the Earth from solar coronal holes?
A. HF communications are improved
B. HF communications are disturbed
C. VHF/UHF ducting is improved
D. VHF/UHF ducting is disturbed
• (B)]
• The corona is the Sun’s outer layer. Temperatures in the corona are typically about two million degrees Celsius, but can be more than four million degrees Celsius above an active sunspot region. A coronal hole is an area of somewhat lower temperature. Matter ejected through such a “hole” is in the form of plasma, a highly ionized gas made up of electrons, protons and neutral particles. The plasma travels at speeds up to two million miles per hour, and if the “jet” of material is directed toward the Earth it can result in a geomagnetic storm on Earth, disrupting HF communications.
16. G3C04 What does the term “critical angle” mean as used in radio wave propagation?
A. The long path azimuth of a distant station
B. The short path azimuth of a distant station
C. The lowest takeoff angle that will return a radio wave to the Earth under specific ionospheric conditions
D. The highest takeoff angle that will return a radio wave to the Earth under specific ionospheric conditions
• (D)
• At each frequency there is a maximum angle at which the radio wave can leave the antenna and still be refracted back to Earth by the ionosphere instead of simply passing through it and proceeding out into space. The critical angle changes depending on the ionization of the ionosphere.
17. G3C09 What type of radio wave propagation allows a signal to be detected at a distance too far for ground wave propagation but too near for normal sky-wave propagation?
B. Scatter
D. Short-path skip
• (B)
• The area between the farthest reach of ground-wave propagation and the point where signals are refracted back from the ionosphere (sky-wave propagation) is called the skip zone. Since some of the transmitted signal is scattered in the atmosphere, communication may be possible in the skip zone by the use of scatter signals.
18. G4A07 What condition can lead to permanent damage when using a solid-state RF power amplifier?
A. Exceeding the Maximum Usable Frequency
B. Low input SWR
C. Shorting the input signal to ground
D. Excessive drive power
• (D)
• Transistors are more sensitive to input drive levels than the more rugged vacuum tubes and can be damaged very quickly if too much power is applied. Fast-acting control circuits are required to protect the transistors from excessive drive.
19. G4A08 What is the correct adjustment for the load or coupling control of a vacuum tube RF power amplifier?
A. Minimum SWR on the antenna
B. Minimum plate current without exceeding maximum allowable grid current
C. Highest plate voltage while minimizing grid current
D. Maximum power output without exceeding maximum allowable plate current
• (D)
• The Tune control of a vacuum tube RF amplifier--either of a standalone amplifier or of a transmitter output stage--adjusts the impedance matching circuit at the frequency of operation. Adjusting the Tune control for a pronounced “dip” in plate current indicates that the circuit is set for the right frequency. The Load or Coupling control is then used to adjust the amount of output power. The Tune and Load controls are alternately adjusted until the required amount of output power is obtained without exceeding the tube’s plate current rating.
20. G4B11 Which of the following must be connected to an antenna analyzer when it is being used for SWR measurements?
B. Transmitter
C. Antenna and feed line
D. All of these choices are correct
• (C)
• An antenna analyzer is the equivalent of a very low-power, adjustable-frequency transmitter and SWR bridge. The antenna and feed line are connected to the analyzer and SWR measurements are made directly from the analyzer’s meter or display while the analyzer frequency is adjusted. This is much more convenient than using a transmitter and wattmeter and also minimizes the potential for interfering with other signals.
21. G4C05 What might be the problem if you receive an RF burn when touching your equipment while transmitting on an HF band, assuming the equipment is connected to a ground rod?
A. Flat braid rather than round wire has been used for the ground wire
B. Insulated wire has been used for the ground wire
C. The ground rod is resonant
D. The ground wire has high impedance on that frequency
• (D)
• One purpose of an amateur station’s RF ground system is to make sure that unwanted signals, such as those picked up from your own transmissions, are directed to ground instead of flowing on or between pieces of equipment. If the ground wire is long enough to be resonant on one or more bands, however, it will present a high impedance, which can enable high RF voltages to be present on the chassis of your equipment or microphone. This can cause an RF burn if the “hot spot” is touched when you are transmitting.
22. G5A05 How does an inductor react to AC?
A. As the frequency of the applied AC increases, the reactance decreases
B. As the amplitude of the applied AC increases, the reactance increases
C. As the amplitude of the applied AC increases, the reactance decreases
D. As the frequency of the applied AC increases, the reactance increases
• (D)
• The opposition to flow of current caused by the coil in an alternating current (ac) circuit is referred to as inductive reactance. Inductive reactance increases as the ac frequency increases.
23. G5A06 How does a capacitor react to AC?
A. As the frequency of the applied AC increases, the reactance decreases
B. As the frequency of the applied AC increases, the reactance increases
C. As the amplitude of the applied AC increases, the reactance increases
D. As the amplitude of the applied AC increases, the reactance decreases
• (A)
• The opposition to flow of current caused by a capacitor in an alternating current (ac) circuit is referred to as capacitive reactance. This reactance decreases as the ac frequency increases.
24. G5B06 What is the output PEP from a transmitter if an oscilloscope measures 200 volts peak-to-peak across a 50-ohm dummy load connected to the transmitter output?
A. 1.4 watts
B. 100 watts
C. 353.5 watts
D. 400 watts
• (B)
25. G5B11 What is the ratio of peak envelope power to average power for an unmodulated carrier?
A. .707
B. 1.00
C. 1.414
D. 2.00
• (B)
• It’s 1.0 because for an unmodulated carrier all RF cycles have the same voltage, meaning that the envelope’s average and peak values are the same.
26. G5B12 What would be the RMS voltage across a 50-ohm dummy load dissipating 1200 watts?
A. 173 volts
B. 245 volts
C. 346 volts
D. 692 volts
• (B)
• It’s 245 V because P = E2 / R, so E = √(1200 / 50). This is the RMS voltage across the 50-W load.
27. 5B13 What is the output PEP of an unmodulated carrier if an average reading wattmeter connected to the transmitter output indicates 1060 watts?
A. 530 watts
B. 1060 watts
C. 1500 watts
D. 2120 watts
• (B)
• The PEP and average power of an unmodulated carrier are the same. For an unmodulated carrier all RF cycles have the same voltage, meaning that the envelope’s average and peak values are the same.
28. G5B14 What is the output PEP from a transmitter if an oscilloscope measures 500 volts peak-to-peak across a 50-ohm resistor connected to the transmitter output?
A. 8.75 watts
B. 625 watts
C. 2500 watts
D. 5000 watts
• (B)
• PEP = (ERMS)2 / R = (250 x 0.707)2 / 50 = 625 W
29. G5C06 What is the RMS voltage across a 500-turn secondary winding in a transformer if the 2250-turn primary is connected to 120 VAC?
A. 2370 volts
B. 540 volts
C. 26.7 volts
D. 5.9 volts
• (C)
30. G5C07 What is the turns ratio of a transformer used to match an audio amplifier having a 600-ohm output impedance to a speaker having a 4-ohm impedance?
A. 12.2 to 1
B. 24.4 to 1
C. 150 to 1
D. 300 to 1
• (A)
31. G7B11 For which of the following modes is a Class C power stage appropriate for amplifying a modulated signal?
A. SSB
B. CW
C. AM
D. All of these choices are correct
• (B)
• A Class C amplifier conducts current during less than half of the input signal cycle, resulting in high distortion. This rules out Class C amplifiers for any form of amplitude modulation, such as SSB or AM. Class C amplifiers can be used for CW since that mode requires only the presence or absence of a signal. Similarly, Class C is suitable for FM signals that only depend on signal frequency, which is not changed by the amplifier. Class C amplifiers generate significant harmonics, so they require filtering for use as transmitter outputs.
32. G7C03 What circuit is used to process signals from the RF amplifier and local oscillator and send the result to the IF filter in a superheterodyne receiver?
A. Balanced modulator
B. IF amplifier
C. Mixer
D. Detector
• (C)
• In a superheterodyne receiver, the mixer combines signals from the RF amplifier and the local oscillator (LO) then sends those signals to the IF filter, which passes the desired range of frequencies while rejecting the signals at higher and lower frequencies.
33. G7C06 What should be the impedance of a low-pass filter as compared to the impedance of the transmission line into which it is inserted?
A. Substantially higher
C. Substantially lower
D. Twice the transmission line impedance
• (B)
• To prevent unwanted reflected power and elevated SWR, keep all elements of the feed line and antenna system at the same impedance. A low-pass filter, designed to be installed at the transmitter output, should have the same impedance as the transmission line.
34. G7C07 What is the simplest combination of stages that implement a superheterodyne receiver?
A. RF amplifier, detector, audio amplifier
B. RF amplifier, mixer, IF discriminator
C. HF oscillator, mixer, detector
D. HF oscillator, pre-scaler, audio amplifier
• (C)
• By definition, a superheterodyne receiver must contain a mixer and a local oscillator. One additional stage, a detector, is necessary to recover the modulating audio. Thus, the simplest superheterodyne consists of a mixer, oscillator, and detector. Practical receivers add more amplifiers to improve sensitivity and filters to reject unwanted signals.
35. G8A10 What is meant by flat-topping of a single-sideband phone transmission?
A. Signal distortion caused by insufficient collector current
B. The transmitter's automatic level control is properly adjusted
C. Signal distortion caused by excessive drive
D. The transmitter's carrier is properly suppressed
• (C)
• The figure shows an overmodulated signal (B) as seen on an oscilloscope with flattening at the maximum levels of the envelope. This is referred to as flat-topping.
36. G9B10 What is the approximate length for a 1/2-wave dipole antenna cut for 14.250 MHz?
A. 8 feet
B. 16 feet
C. 24 feet
D. 32 feet
• (D)
• In free space, ½ wavelength in feet equals 492 divided by frequency in MHz. If you cut a piece of wire that length, however, you’ll find it is too long to resonate at the desired frequency. A resonant ½-wave dipole made of ordinary wire will be shorter than the free-space wavelength for several reasons. First, the physical thickness of the wire makes it look a bit longer electrically than it is physically. The lower the length-to-diameter (l/d) ratio of the wire, the shorter it will be when it is resonant. Second, the dipole’s height above ground also affects its resonant frequency. In addition, nearby conductors, insulation on the wire, the means by which the wire is secured to the insulators and to the feed line also affect the resonant length. For these reasons, a single universal formula for dipole length, such as the common 468/f, is not very useful. You should be start with a length near the free-space length and be prepared to trim the dipole to resonance using an SWR meter or antenna analyzer. The exam only requires that you identify an approximate resonant length for a dipole. Use the free-space length, calculated as 492 / f (in MHz), and select the closest choice. In this case, length (feet) = 492 / 14.250 = 34.5 feet, so select the closest value; 32 feet.
37. G9C12 Which of the following is an advantage of using a gamma match for impedance matching of a Yagi antenna to 50-ohm coax feed line?
A. It does not require that the elements be insulated from the boom
B. It does not require any inductors or capacitors
C. It is useful for matching multiband antennas
D. All of these choices are correct
• (A)
• One major advantage of the gamma match is that the driven element does not have to be insulated from the antenna’s boom. This simplifies mounting the element and leads to a sturdier antenna.
38. G9D05 What is the advantage of vertical stacking of horizontally polarized Yagi antennas?
A. Allows quick selection of vertical or horizontal polarization
B. Allows simultaneous vertical and horizontal polarization
C. Narrows the main lobe in azimuth
D. Narrows the main lobe in elevation
• (D)
• The increase in gain for a vertical stack of Yagi antennas results from narrowing the vertical width of the main or major lobe of a single antenna’s radiation pattern. The narrower lobe results in stronger received signals and less received noise at angles away from the peak of the main lobe.
 Author: rledwith ID: 227016 Card Set: General Exam-Missed Questions-1 Updated: 2013-07-23 14:49:19 Tags: rdl gen exam missed Folders: Description: Amateur Radio General Exam - G11 Question Set - Missed Questions-1 Show Answers: